Unvented Config Advice

[soul2soul]

Hi All,

We are in the process of getting our bathroom redone & it has currently been stripped to it's shell. We have an unvented Santon tank loacted in the loft that was fitted last year.

As part of this refurb we need to move the mains supply pipe to the tank in the loft onto a different wall in the bathroom. The plumber has suggested that it is better for the cold mains feed to go to the unvented in the loft first the balance the cold feed out from there back into the bathroom. This is opposed to the current set up of the bathroom being supplied by the current cold feed on it's way up to the unvented.

Is there any real benefit in doing it this way as it strange to me to bybass the bathroom cold outlets then go up into the loft only for it to come back down into the bathroom again?

Thanks in advance

 

[kevplumb]

Is there any real benefit in doing it this way as it strange to me to bybass the bathroom cold outlets then go up into the loft only for it to come back down into the bathroom again?

balanced supplys better for showers etc

 

[linkyplumb]

Hi
It depends what you are going to have in your bathroom.
If you are having a shower then it is beeter to balance the cold and hot, as you will get a nice balanced shower.
The same with the taps.If they are mixer taps then the balanced option is better.
Also what type of types are you having- HIgh or low pressure?
Graham

Damn Kev beat me again.... must stop typing one fingered

 

[soul2soul]

Is there any real benefit in doing it this way as it strange to me to bybass the bathroom cold outlets then go up into the loft only for it to come back down into the bathroom again?

balanced supplys better for showers etc

Can you expand a bit on that for me please as I am a plumbing novice!
My main concern is that I could be losing out on the cold pressure since it is going up another floor, round that floor a bit then back down into the bathroom when it passes the bathroom feeds on it's way up to the tank.

We have a thermostatic shower in the bathroom & it seemed to work ok on the original set up.

Just want to be sure that it gets done the best way whilst I have the opportunity

 

[soul2soul]

Hi
It depends what you are going to have in your bathroom.
If you are having a shower then it is beeter to balance the cold and hot, as you will get a nice balanced shower.
The same with the taps.If they are mixer taps then the balanced option is better.
Also what type of types are you having- HIgh or low pressure?
Graham

Damn Kev beat me again.... must stop typing one fingered

All high pressured & mixer taps in the bathroom as well as an Aqualisa Thermostatic Shower

 

[kevplumb]

incoming water pressure say 3 bar hypothetically

it goes through the cylinder pressure reducing valve down to say 1 bar

so you now have cold at 3 bar , hot at 1 bar

if the cold feed comes off after the prv

both supplies are balanced at 1 bar

 

[soul2soul]

incoming water pressure say 3 bar hypothetically

it goes through the cylinder pressure reducing valve down to say 1 bar

so you now have cold at 3 bar , hot at 1 bar

if the cold feed comes off after the prv

both supplies are balanced at 1 bar

Excuse my ignorance but does that no mean that the water pressure to the shower will be less than 3 bar hot & 1 bar cold meaning worse shower performance?

 

[kevplumb]

using the figs i did

it will be 3 bar COLD 1 hot

 

[soul2soul]

using the figs i did

it will be 3 bar COLD 1 hot

Sorry just to confirm if I balance my cold feed I will not get a reduction in pressure to the shower opposed to me not balancing it?

 

[TicklyT]

Unless you use a venturi shower, increasing the cold pressure above the hot pressure just makes for a cold shower!

As soon as the dynamic cold pressure in the mixer valve body exceeds the hot pressure, the hot water flow will stop, or may even be forced back the way it came, overpressurising the hot store.

So there's no gain in using unbalanced pressures, just a possible hatfull of headaches.

 

[snb]

where is the current pressure reducing valve?
is next to the tank or is it straight after your mains stopcock?


if it is after the stopcock then no worries as the whole house would be at the reduced pressure (max normally of 2.5bar).

if at the tank then it would be best to put in the balanced supply

 

[kevplumb]

it will be near the cylinder

 

[Nige F]

Another distrusting OP. Don`t worry about the plumbers ...worry about the "gas fitters"

 

[kevplumb]

behave you

 

[soul2soul]

where is the current pressure reducing valve?
is next to the tank or is it straight after your mains stopcock?


if it is after the stopcock then no worries as the whole house would be at the reduced pressure (max normally of 2.5bar).

if at the tank then it would be best to put in the balanced supply

Sorry guys been away from the PC most of the weekend.
The PRV is next to the tank in the loft.

Thanks for all your help with this & giving me comfort that I am getting it done the right way by balancing it.


Just out of curiosity how come the shower seemed to work fine when the system was not balanced?